(i) Field of the Invention
This invention relates to a die registration system.
(ii) Description of the Prior Art
The dies with which the present invention is principally concerned are rotary dies of all sizes for the processing of corrugated board from E flute to double wall. Such dies are computer designed and generated.
A rotary die generally consists of a wood base having a series of slots cut therethrough into which cutting steel strips are inserted. Thereafter, the tool is attached to a rotating press and is used in the manufacture of paper products, e.g., boxes, cartons, etc.
In the past, the die, or a part thereof, in cases where a complete die consist of several adjacent parts, was mounted with reference to a key eye arrangement at the centre and bottom of the die. A reference bolt was provided on a steel roller blank. Thereafter, various circular holes in the die were aligned with a pre-arranged pattern of holes on the steel roller blank of the rotary press to secure the die to the steel roller blank. The pre-arranged hole pattern could be any pattern. In the past, however, it usually consisted of drilled holes spaced about two inches apart in both the linear (axial) direction and along the circumference of the steel roller blank. In mounting the die, the datums or reference points were picked off the key eye which established the mounting datums.
It was found, however, that, in the mounting of the die, a problem of skewing occurred. In other words, the die moved slightly along the base upon which it was mounted. Any skewing compounded the error the further removed a point was from the key eye datums reference point.